Answer: 75%
Step-by-step explanation:
Set up a Punnett square with both parents having the Tt genotype. The 4 offspring will have the genotypes TT, Tt, Tt, and tt.
Since T is dominant, all offspring that carry at least 1 copy of it will exhibit the trait. 3/4 of the offspring carry at least 1 copy of T, so 3/4 or 75% of the offspring will exhibit the dominant trait.